The present invention relates to orthopedic fixation systems, assemblies, devices and related methods for reduction of a fractured bone of a patient.
Reduction is a medical procedure to restore a fracture or dislocation to the correct alignment. When a bone fractures, the fragments lose their alignment in the form of displacement or angulation. For the fractured bone to heal without substantial deformity the bony fragments must be re-aligned to their normal anatomical position. Orthopedic surgeons attempt to recreate the normal anatomy of the fractured bone by reduction.
Fractured bone reduction or treatment can include use of fixation methods that can reinforce the fractured bone and keep it aligned during healing, including use of external devices or casts as well as internal devices such as rods, bone plates and/or fasteners. Under certain circumstances, a physician may decide that external fixation is the best treatment for a patient. Fixation with external devices and assemblies includes surgical techniques for setting bone fractures and/or for limb lengthening that was first used more than a century ago. Since that time, the technique has evolved from being used primarily as a last resort fixation method to becoming a main stream technique used to treat a myriad of bone and soft tissue pathologies.
In some cases, external fixation can be accomplished by placing pins or screws into the bone of a patient and securing the pins through the use of an external frame assembly positioned at least partially outside the body. During the treatment, the external frame can hold bone fragments at adjustable spacing and angles to create a desired overall bone length and angular disposition of the bone fragments. To connect the external fixation device to the bone, pins can be placed, for example, on either side of the break in the bone and pass through the skin and sometimes the muscles. Sometimes wires can also be used with the pins, or in place of pins, to secure the bone pieces. The pins and/or wires can hold the bone in place and anchor the fixator securely, while also avoiding damage to vital structures, allowing access to the area of injury, and meeting the mechanical demands of the patient and the injury. Treatment using external fixation can take about 6 weeks for a simple fracture, and up to one year or longer for a more complicated fracture.
As compared to other fixation methods, external fixation devices can provide numerous advantages. When compared with internal plates and intramedullary nails, for example, external fixators can cause less disruption of the soft tissues, osseous blood supply, and periosteum. Accordingly, external fixation devices can be useful for soft tissue management in the setting of acute trauma with skin contusions and open wounds, in chronic trauma where the extremity is covered in thin skin grafts and muscle flaps, and in patients with poor skin whose healing potential is compromised as in the case of rheumatoid disease, peripheral vascular disease, diabetes mellitus, and Charcot disease. In addition, the temporary nature of the pins and wires can provide bony stability in the setting of osteomyelitis where the presence of internal implants make eradication of infection more challenging. The ability to avoid putting fixation into the infected area is equally beneficial.
Unlike internal plates and intramedullary nails, external fixators also provide postoperative adjustability. This allows the extremity to be manipulated in the operating room to gain exposures to fracture fragments. In the situation of limb lengthening or deformity correction, gradual manipulation is possible with frame adjustment over time. As a result, external fixations have found use in pediatric fracture care where open physes preclude intramedullary nailing. Leg length discrepancy can also be reliably treated with circular and monolateral design fixators.
Despite these advantages, existing external fixation devices and assemblies still remain limited in their application for treatment of bone fractures. For example, while the devices known in the prior art can help provide valuable treatment of fractures, particularly in the surgical setting, existing devices can be somewhat cumbersome and limited in versatility. Thus, there is continued interest in providing improved external fixation devices that are more versatile and can be used, for example, as more ambulatory or portable devices.